Wikipedia:Reference desk/Archives/Science/2006 June 24

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Help Me Identify This Butterfly[edit]

On my photographs page, I have added a picture of a butterfly that I took this morning. The picture was taken in New York City, and I'm interested in what it is. Thanks to anyone who can help! M@$+@ Ju ~ 00:54, 24 June 2006 (UTC)[reply]

That's a black swallowtail, resting on a purple coneflower (echinacea)--Mark Bornfeld DDS 03:03, 24 June 2006 (UTC)[reply]
Awesome! Thanks alot for your help :) M@$+@ Ju ~ 03:26, 24 June 2006 (UTC)[reply]

Ice cubes[edit]

Why do my ice cubes come out of their trays crushed sometimes and whole other times? --24.209.166.131 03:47, 24 June 2006 (UTC)[reply]

When water frees, it expands. This can result in ruptures in the cube, and can even cause a spike to form in the center. If the freezing happens from the bottom up, however, the water level will just rise and a nice cube will be formed. How the ice tray cubes are placed in the freezer, and how close they are to the cooling elements and other items, may affect the direction in which the cubes freeze. StuRat 03:52, 24 June 2006 (UTC)[reply]

Depends a lot on from where the cold source is coming from. --Proficient 17:40, 24 June 2006 (UTC)[reply]

Neuroprosthetics or Neuro cybernetics[edit]

I have checked both pages on Neuroprosthetics and Neuro cybernetics, but am I still not sure of the following.

I want a career in Neurology, but am not sure of the exact one. I want to be able to study making machines work with human and animal brains, and other parts of the central nervous system, such as virtual reality or machines that "alter" the mind in order to create a false reality. I have narrowed it down to either Neuroprosthetics or Neuro cybernetics, but I still can't figure out which one best fits that description. Can somebody please tell me which title, Neuroprosthetics, Neuro cybernetics, or something else best fits that description? Thank you.

Sincerely, --Dac011893 03:54, 24 June 2006 (UTC)[reply]

I would think the neuro-cybernetics would be closer to what you want. This might include things like the new process for implanting electrodes into the brain so blind people can "see" using a video camera. StuRat 04:10, 24 June 2006 (UTC)[reply]

Okay. Thank you. --Dac011893

I'm not sure if this helps, but where I work (Boston University), the department in which work that is most similar to what you're asking about takes place is called Biomedical Engineering (BME). I'm specifically thinking of John White's work on the dynamic clamp, which allows one to interface a computer with real neurons, such that the computer basically simulates extra neurons and machines provide the input/output between the real and simulated neurons. I'm know there are labs that do work more similar to what you're asking, but I don't know of them personally so I can't really say much about them. Nevertheless, you may want to at least look at biomedical engineering to get other ideas. 128.197.81.181 15:51, 24 June 2006 (UTC)[reply]

Thank you. I clicked on the link and it stated that "It has been suggested that Neuro cybernetics be merged into this article or section," so I would assume that they are similar fields and probably include work from one another, and possibly are the same thing at their cores. Thanks again. --Dac011893

Magnetic fields[edit]

I know that a moving electric current creates a magnetic field, but why?

Gooood question. I think the answer has something to do with tensors, something about how the electric and magnetic fields are really parts of one complex tensor field. I think it also has to do with special relativity, because if you're moving along with the charge then in your reference frame it's at rest, so there's no magnetic field, but if you're moving relative to it, then spacetime is all shifted so there is a magnetic field. Someone more advanced in physics than I should probably handle this one... —Keenan Pepper 04:35, 24 June 2006 (UTC)[reply]
Anyone?? —Keenan Pepper 17:21, 24 June 2006 (UTC)[reply]
I can't wait for a suitable answer ;) —GTubio 21:57, 24 June 2006 (UTC)[reply]
Thats almost completely correct Keenan Pepper, and it's explained (slightly) in Maxwell's equations and Magnetic field. Using vector calculus, you can split up the electric field of the current into a stationary electric field, and a stationary magnetic field. That's just a mathematical way of demonstrating the fact that they are part of a rank-2 tensor.
To quote... "In relativity, the equations are written in an even more compact, "manifestly covariant" form, in terms of the rank-2 antisymmetric field-strength 4-tensor that unifies the electric and magnetic fields into a single object." --Eh-Steve 13:40, 26 June 2006 (UTC)[reply]

Thanks for actually taking your time and explaining it to me but can you explain it in layman's terms? Thanks!

How about this: if we remove all the metal and positive ions from an electric circuit and just leave the flowing electrons, those electrons will produce an immense electrostatic field or "e-field," ...but because they are moving, the e-field will be distorted in an odd way. The distortion vanishes if you walk along at the same speed as these electrons (since after all, motion is relative, so when you follow the electrons, from your viewpoint they're not moving.) OK, now put the positive metal ions back into the wires. The positives cancel out the negatives; the huge e-field is gone, but the motion-distorted part of the field is still there. (To get rid of the odd distortion, the positives and negatives would both have to flow along together, and in that case the electric current in the wire would be zero.) We call this residual e-field distortion by the name "magnetic field." However, there's another effect too: if you walk along at the same speed as the electrons in the wire, the distortion doesn't go away ...since from your point of view the positive metal ions are now moving backwards, and they produce an electric current and a similar type of distortion. --Wjbeaty 03:45, 26 June 2006 (UTC)[reply]

Solid eggs[edit]

What's the freezing point of a chicken egg? Is there anything else that could cause an egg to solidify in a refrigerator? --67.185.172.158 04:46, 24 June 2006 (UTC)\[reply]

The shell seems to thin and would appear to easily break if frozen. --Proficient 17:53, 24 June 2006 (UTC)[reply]
The freezing point of what kind of egg? Hard-boiled? Scrambled? Raw? A chicken egg? Crocodile, ostrich? — The Mac Davis] ⌇☢ ญƛ. 18:46, 24 June 2006 (UTC)[reply]
Supposedly-raw chicken eggs. I've got a dozen eggs in my refrigerator that pass the "hard-boiled" test, despite never having been cooked. Cracking one open (with great difficulty) revealed a mostly-solid, translucent yellow mass. --67.185.172.158 06:05, 25 June 2006 (UTC)[reply]

If your milk is OK (no ice) then maybe you've got freaky eggs... otherwise, turn down the power dial. The sides of the fridge are cooler than the middle. --Username132 (talk) File:United Kingdom File:Netherlands 00:46, 3 July 2006 (UTC)[reply]

Different stuff in your eggs would have different freezing points. -- Миборовский 00:22, 26 June 2006 (UTC)[reply]

Part 15 of the FCC rules.[edit]

Why is it so important that FCC rules require electrical devices to accept interference that may cause undesired interference? I'm a science teacher and when one of my students asked me this question, I had no clue. I've searched a bit, but the only explanations I have found pertain to causing inteference.

Here's the standard language found on many consumer electronics: This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) This device must accept any interference received, including interference that may cause undesired operation. User101010 05:14, 24 June 2006 (UTC)[reply]

Isn't this a linguistic thing? Doesn't "must accept" here mean "must be able to deal with"?
By the way, are you as generous to your pupils or do you only give yourself all tens? :) DirkvdM 06:50, 24 June 2006 (UTC)[reply]
I don't give grades. I just assign whatever grade the student earns. Tens are rare from me, mainly because I grade everything on a 100 point scale.  ;-) User101010 00:53, 25 June 2006 (UTC)[reply]
I don't think that's a "linguistic thing". There are many clearer ways of stating it if "must be able to deal with" is what the phrase is supposed to mean. The language of the certification makes you wonder what not accepting interference may mean, since, apparently, having "undesired operation" is still within the meaning of "accepting any interference received".
It looks to me as if the Rules (PDF here, by the way) are badly worded. The statement that User101010 correctly quoted is from Section 15.19 (Labelling requirements), and it doesn't make sense. However, if you look at Section 15.5 (General conditions of operation), it says something similar, except that it is the "operator" who must not cause harmful interference and must accept interference from other sources. I think that someone has clumsily cut and pasted 15.5 into 15.19, changed the implied "operator" to "device", and not noticed that the result is gibberish. This may be because the Rules were originally aimed at radio operators who knew what they were doing, but have been hastily adapted to the modern world in which every gadget is suddenly a source and sink of RFI.
I think the FCC confused themselves by their over-use of the passive voice, so that they forgot who the subject of the sentence was. So, in conclusion, the statement should have said, "You, the owner, must operate this device so that it does not cause harmful interference. If it does, then it's your fault for switching it on, not ours for designing it badly. If it picks up interference from other devices, even if that causes undesired operation, then that's your problem too." --Heron 16:18, 24 June 2006 (UTC)[reply]
Good wording. --Proficient 17:55, 24 June 2006 (UTC)[reply]

A quick clarification... you can find this statement on the bottom of many consumer electronics such as CD players, radios, electronic games, etc. That is why I (and my student) are asking. User101010 00:53, 25 June 2006 (UTC)[reply]

You sound as if you don't consider your question to have been answered yet. Let me try again. The FCC allows manufacturers to sell products that both produce and suffer from interference, as long as the manufacturers put this standard disclaimer on their products. The disclaimer tells the user that it is his responsibility if the device causes interference, and that he or she must "accept" any problems caused by interference affecting his device. That way, he or she can't sue the FCC for failing to enforce the radio regulations. The manufacturer is also happy because it absolves him from responsibility for what the product might do. Presumably there are limits to what you can get away with under a disclaimer, but that's another matter. Have we answered your question yet? --Heron 17:15, 25 June 2006 (UTC)[reply]
That does help, thanks!  ;-) User101010 21:01, 25 June 2006 (UTC)[reply]
Another way to describe the situation is that the FCC licenses radio transmitters. For those transmitters that have a full-fledged license, such as broadcast stations, police transmitters, ham transmitters, etc., they can operate their transmitters according to the rules in the appropriate part of the FCC rules, even if it causes some interference. It is up to the manufacturers of electronic devices to block interference from licensed transmitters, and if they don't, the owner of the device should complain to the manufacturer, not to the operator of the transmitter. (But the transmitter operator is responsible to make sure the transmitter is operating correctly.)
Also, the part 15 device may transmit a small amount of radio energy, but part 15 gives these transmitters the least privileges of any transmitter; essentially, if the device bothers anyone, the operator must turn it off. Gerry Ashton 15:39, 2 July 2006 (UTC)[reply]

Has anyone ever disproven this idea?[edit]

Is it possible that all identical isotopes have the same life span and were simply created at random times and therefore appear to have random life spans? Has anyone ever disproven that what many consider to be entirely random decay occurs instead at exactly the same interval from the moment the isotope was created? ...IMHO (Talk) 08:34, 24 June 2006 (UTC)[reply]

If your theory would be correct, I am quite sure that someone would have proven it already. Thus, most likely, it is not correct. --Andreas Rejbrand 08:55, 24 June 2006 (UTC)[reply]
Perhaps this explains why we find outselves living in a world in which only certain prized individuals are allowed to invent anything or at least to receive the credit. ...IMHO (Talk)
Credit is more complicated than just coming up with it first, but in any case all he is saying is "If it were that simple, then someone else would have already figured it out by now." It's not a rigorous way to disprove something but as a rough heuristic it often works. --Fastfission 17:29, 24 June 2006 (UTC)[reply]
Routine neutron activation work rules out your idea. Dragons flight 09:34, 24 June 2006 (UTC)[reply]
Please explain how neutron activation would rule out a uniform interval between isotope creation and termination except by interuption of the interval. ...IMHO (Talk) 10:11, 24 June 2006 (UTC)[reply]
Simple, I create a sample of radioisotopes over say a day of irradiation, and then watch them decay with a characteristic half life over weeks, months, or years afterwards. By tracking characteristic gamma rays I can tell which isotope is decaying and control for contamination. If your idea was correct they should all decay at once, not exponentially distributed over a long period. Dragons flight 15:59, 24 June 2006 (UTC)[reply]
So you are essentually citing a similar process as when I "irradiate" a luminus dial and watch its intensity of emission decline exponentially. Is that correct? ...IMHO (Talk) 16:09, 24 June 2006 (UTC)[reply]
Qualitatively similar, yes. Dragons flight 16:35, 24 June 2006 (UTC)[reply]
There are aspects of the process which are similar. (Assuming you're talking about a phosphorescent watch dial, and not one of the old tritium-based ones.) Exposure of the dial to light excites molecules of a phosphorescent chemical. Most of them will (virtually) immediately decay back to their ground state, releasing a fluorescence photon and storing no energy. A few will undergo intersystem crossing while in their excited state, and get trapped in a quantum state where the decay back to ground is forbidden under quantum mechanics. (The longer you illuminate the dial, the more molecules will end up trapped in this excited state.) In practice this just makes those excited states very long-lived (a long half-life), resulting in a slow trickle of light as they return to ground state. The math is the same as for radioactive decay, in terms of modelling the process. Note, of course, that the physical processes are very different. TenOfAllTrades(talk) 16:52, 24 June 2006 (UTC)[reply]
Nuclear waste takes tens of thousands of years to decay, if your theory were correct it would have taken tens of thousands of years to make, and it didn't. Thats an obvious example, but more obviously, all substances start to decay immediately, meaning some atoms have decayed in fractons of a second, which would mean that some process would have to bee continually making atoms to decay, if they decayed after one second, and the half life was longer. Philc TECI 10:05, 24 June 2006 (UTC)[reply]
You have misunderstood the question. ...IMHO (Talk) 10:12, 24 June 2006 (UTC)[reply]
Please don't delete my posts, if they are legitimate you have no right too. If your so sure I don't know what you're on about, try making the question less ambiguous. I'm pretty sure I do understand the question, you are asking how can it be proven halflives are random, and not just that the isotopes were created and differing times. If not please explain what you mean. Philc TECI 17:24, 24 June 2006 (UTC)[reply]
My point is if you are right explain this. Nuclear waste is created, over a period of ten years, when it leaves the reactor it has already begun decaying, and takes 50,000 years to decay to an acceptable level. THEREFORE: the interval between the creation and decay of the atoms that were decaying when it left the reactor is maximum ten years and the interval between when it left the reactor and when it had decayed to an acceptable level is minimum 50,000 years. IN DEDUCTION: 10 year period of creation --> minimum 50,000 year period of decay.
No. Radionuclides produced for use in nuclear medicine (e.g. positron emission tomography) decay according to their accepted half-lives, not all at once. EdC 13:46, 24 June 2006 (UTC)[reply]
Can you name the experiment in which Radionuclides were produced where 1.) only a single isotope was produced (i.e,. no impurities are included), and 2.) there is a record of the exact moment each individual atom was created and later the moment of each atom's decay? ...IMHO (Talk) 14:44, 24 June 2006 (UTC)[reply]
No, and I don't need to. Radionuclides produced in a cyclotron are created at constant rate over a short period of time. If your idea was correct the decay curve would be hat-shaped; it's not, it's exponential. Although, you might look for papers on the production of the transuranides and the calculation of their half-lives; some of those were produced in single-figure amounts. EdC 23:19, 24 June 2006 (UTC)[reply]
Isotopes (I'm assuming you mean atomic nuclei) are composed of smaller particles, so it's not clear how you would define the time when they are "created". Peter Grey 13:58, 24 June 2006 (UTC)[reply]
Yes it is. When the protons and neutrons were created is immaterial. They are proposing that each atomic nucleus will decay after the same time interval as every other atomic nuclei of the same isotope. This is incorrect, however, since we can create nuclei in a lab at a specific time and watch how long they take to decay, and have determined that this period is not constant for each isotope. StuRat 14:12, 24 June 2006 (UTC)[reply]
With that definition, there's nothing random about the creation time. Half-life decay has pretty simple math, and you could argue the conjecture was disproved as soon as they figured out the behaviour of radioactivity (over 100 years ago). Peter Grey 02:44, 25 June 2006 (UTC)[reply]
Here's a snippet from usenet that I found on the subject: "Spontaneous radioactive decay is governed by second order perturbation theory which produces a Lorentzian energy spectrum whose Fourier transform to the time domain is a simple exponential, which results in a constant per unit time probability for a decay transition.
"A constant per unit time probability is the essence of a true random process, namely the decay for any given nucleus can happen any time with equal probability. The Lorentzian line shape has been directly observed experimentally in the Mossbauer Effect and so has the exponential in time. That puts the theory on solid experimental ground." source: [1]
The poster provided no references, but I'm sure you can look up the appropriate terms and come across suitable experiments that have been done. 128.197.81.181 16:06, 24 June 2006 (UTC)[reply]

Here's some evidence that radionuclides do not have a single decay-time: Nearly all of the heavy elements in our solar system, including the radioactive ones, were probably produced in a short cataclysmic supernova. Therefore by the idea posed one would expect them all to catastrophically decay at one, probably vaporizing large parts of the earth. Instead we experience the phenomenon of radioactivity, which is the slow, steady, random decay of heavy elements. That is, they were pretty much all created at once, so they would pretty much all decay at once.--Bmk 04:15, 26 June 2006 (UTC)[reply]

  • Both you and StuRat seem to have somehow missed what I am asking. Its not that all isotopes might might have the same duration but rather that each atom of each isotope would have the same duration and a different moment of creation. For instance: Carbon-14 is probably produced by supernovas but we know that it is also a product of cosmic ray bombardment of Nitrogen-14 in the upper atmosphere. Since cosmic ray bombardment has been going on since the big bang and since the Earth has had an atmosphere for a fairly long time that those atoms which are popping Beta particle today which may set off a Geiger counter or other detection device are naturally occuring at random intervals since there has been plenty of elapsed time since their individual creation for mixing such that it would not even be possible to find any material with a group of atoms that were created at the exact same time. However, the question has already been answered above. I just wanted to clear up this misunderstanding of the question at hand in case you were not deliberately misinterpreting it. ...IMHO (Talk) 11:13, 28 June 2006 (UTC)[reply]
I understood what you meant. I did note that the supernova example would result in many huge events as each isotope reached it's age to decay, if your model was correct, and not a single massive decay event, as was stated, however. StuRat 01:21, 29 June 2006 (UTC)[reply]
I think there is a confusion about two meanings of random. Decay events are random, but they are not completely haphazard. They are exponentially distributed, so within limits there is a basis for predicting behaviour, and the mathematics shows pretty definitively that decay events are independent of age. Peter Grey 17:31, 29 June 2006 (UTC)[reply]

technology[edit]

i have heard that a student from electronics/electrical engineering can specialize in computer science laterbut not vice versa. how far is this true?

Well electronics could be a good foundation for computer science - however if you just have learnt programming from a computer course that won't be much use for electronic engineering - you'd have to learn a lot of new stuff.HappyVR 13:53, 24 June 2006 (UTC)[reply]
In most countries, engineering is a regulated discipline, as it is a profession (see ABET and CCPE for examples in North America) and therefore subject to restrictions on cirriculum and so forth. This includes a minimum amount of credits for science and math courses. While usually a CS student can get the required amount of math credits for an engineering degree, CS cirriculums usually don't include enough science to meet the requirements, unless the cirriculum is specifically designed to cover the requirements (eg CS/EE, Computer Engineering and Software Engineering programs). Unless a person takes one of the previous courses, or takes a ton of science courses then wade through a lot of bureaucracy, it's probably very hard for them to switch from CS into engineering without retaking a lot of courses. For an electrical engineering student to specialize in computer science, it usually involves taking some extra computer science courses as their electives, as the restrictions for a CS major, minor, or option are lighter. --ColourBurst 05:56, 25 June 2006 (UTC)[reply]

Cure for a phobia[edit]

Interested in the question above about that irrational fear towards wrists, I was wondering... Are there general cures for phobias? What is, generally speaking, the "method" they follow? Thanks.

Shock treatment has been used to cure fears, though that article is relatively irrelavent to how I mean the term. It is where patients are exposed to excessive amounts of whatever they fear, eg, taking someone with vertigo sky-diving, or hydrophobia deep sea diving. Not sure how you apply this to wrists though. Philc TECI 14:18, 24 June 2006 (UTC)[reply]
Desensitization treatment involves slowly increasing the exposure level so the subject has time to become accustomed to the stimulus. This is quite similar to the method used for allergies, although here it is a mental tolerance which is built up to the stimulus, not a physical one. StuRat 14:57, 24 June 2006 (UTC)[reply]
Those two are pretty much the main two forms of treatment. Shock treatment is sometimes prefered as there is very little scope for backing out, but desensitization treatment is less harsh, and generally preffered due to it's less extreme dosage, I think. Philc TECI 17:16, 24 June 2006 (UTC)[reply]
Gather your friends and wave your wrists in front of the patient. --Proficient 17:57, 24 June 2006 (UTC)[reply]
No, an amateur doing this could just make things worse. If you have a debilitatiing phobia, please go to a professional psychiatrist for treatment.--Pharos 18:37, 24 June 2006 (UTC)[reply]
I saw Paul McKenna do some work on similar cases, he worked by quickly socially conditioning the patient to assiciate things they severly dislike with bad habits, so I guess a similar thing can be done the other way. Philc TECI 22:09, 24 June 2006 (UTC)[reply]
Growing up works on many phobias for many people. (As a child, I was terrified of witches who lived in the space underneath the bathroom sink, when the light was off. Strangely, it doesn't bother me so much any more... they're quite chatty and generally misunderstood, witches.) --Dweller 17:42, 29 June 2006 (UTC)[reply]

Seagulls[edit]

Which is your favourite breed of seagull? I like the great black-backed gull the best. It's like having an albatross in your garden. Big, beautiful bird. --84.66.114.107 11:52, 24 June 2006 (UTC)[reply]

How do you judge the goodness of seagulls? I can't say I've ever had a good experience with a seagull before, people from 'round my parts tend to think of them as pests rather than magestic birds. Personally, I prefer the seagulls I saw in Toronto to the ones in Tokyo, but that's only because they look less menacing to me up close.  freshofftheufoΓΛĿЌ  11:58, 24 June 2006 (UTC)[reply]
With or without gravy ? Actually, my favorite seagull is Jonathan Livingston. StuRat 14:50, 24 June 2006 (UTC)[reply]
Sure, they're noisy, vicious and quarrelsome birds but I think they look handsome, strong, majestic and noble when at rest. They have something of the eagle about them. The babies are really sweet too. --84.66.114.107 16:38, 24 June 2006 (UTC)[reply]
There tends to be a lot of questions asked here about seagulls. ;o --Proficient 17:59, 24 June 2006 (UTC)[reply]
A conspiracy perhaps?  freshofftheufoΓΛĿЌ  06:54, 25 June 2006 (UTC)[reply]
Squawk!! You caught us. Wikipedia is a mind control program run by we seagull overlords.--Bmk 04:17, 26 June 2006 (UTC)[reply]
I for one WELCOME our new seagull overlords!--Quase 03:43, 29 June 2006 (UTC)[reply]
Nice Simpsons ref. StuRat 18:16, 29 June 2006 (UTC)[reply]

Glasses[edit]

Can aesthetic glasses (no corrective lenses) cause eye strain? I've just started wearing glasses (though I've never needed them) and I'm wondering if this pain is just from the weight of the glasses on my nose or from staring into the (flatparallel) lenses.  freshofftheufoΓΛĿЌ  11:58, 24 June 2006 (UTC)[reply]

It's kinda weird wearing glasses for aesthetic reasons.
First of all you say 'flat' lenses - are they actually flat (like a desktop) - I'm guessing not but if they are that will have an optical effect - if you wearing glasses just for aesthetic reasons you should make sure that the 'glass' in the lenses has no effect on your vision (roughly speaking they lenses should be equal thickness and spherical) - suggest you consult an optician for advice.
Secondly - yes as someone who wears glasses - they can be painful - like new shoes - until you get used to them - or if they are a bad pair - always painful. Hope that helps.HappyVR 13:53, 24 June 2006 (UTC)[reply]
Many people wear glasses for aesthetic reasons, take Drew Carey for example. By "flat", I meant that there was no index on the lenses, e.g. no optical effect that you can't see looking through a pane of clear plastic. Is the pain you get from wearing new glasses from the frames or is it a muscle pain in your eyes?  freshofftheufoΓΛĿЌ  14:18, 24 June 2006 (UTC)[reply]
Ha ha! Drew Carey referred to his glasses as "contraceptive glasses". - Cybergoth 16:04, 24 June 2006 (UTC)[reply]
It could be pain from the frames - that's common - the constant pressure on you nose and ears can give rise to pain. If their is no index in the lens you still could get pain in the eyes from having your field of view framed by the frame of the glasses (that could cause a headache) - also if your eyes keep focussing on the frame or reflections in the lens this can cause eye strain too (focusing too close) - causing pain. It could be either - and probably a combination of both - again if you are getting pain from wearing glasses (not just a one off headache) then you should see an 'eye doctor' at least to check that there is nothing wrong with the glasses.HappyVR 14:29, 24 June 2006 (UTC)[reply]
Also even with lenses with no optical effect - if the lenses are not fitted correctly over the center of the eye then they will have a slight effect - which could cause a headache if worn for a long period of time. Different people have different distances between the eyes - if the centre of the lenses are not the same distance apart as the centres of the pupils the 'no index' lenses will act to a small extent - distorting your vision?HappyVR 14:58, 24 June 2006 (UTC)[reply]

Application Error[edit]

Quite often, but not always, when I close my newly installed Internet Explorer 7 Beta window, I get the error message below.

File:Application Error.png

If you are familiar with this problem, then I ask that you suggest a solution.
My operating system is Windows XP Media Center Edition.Patchouli 12:49, 24 June 2006 (UTC)[reply]

if you don't want your browser to crash, I suppose you shouldn't use a Beta version. In fact, you probably shouldn't use IE at all in that case and try an alternative such as Firefox. dab () 14:02, 24 June 2006 (UTC)[reply]
I am also using IE 7 beta 2, and it has “crashed” sometimes during shutdown. My best idea is to wait until the stable version of IE 7 is released. This is a beta, and is “allowed” not to be “perfect”. Mainly, however, I am quite found of Internet Explorer. --Andreas Rejbrand 14:30, 24 June 2006 (UTC)[reply]
IF you're using Media Center Edition, it's hopeless, it's going to keep doing that forever on to infinitie, I've seen the exact same thing happen over and over again on computers with nothing in common other than Media Center--64.12.116.74 16:54, 24 June 2006 (UTC)[reply]
Just downgrade from beta. --Proficient 18:00, 24 June 2006 (UTC)[reply]
  • After clicking okay, I see another small window, which I add hereon.
File:Error 217.JPG
This image is too big.

.Patchouli 01:53, 25 June 2006 (UTC)[reply]

  • I don't know how to crop the image (I pasted it in the Paint program before uploading it).Patchouli 01:55, 25 June 2006 (UTC)[reply]
Googling "CiceroUIWndFrame" (which is clearly the handle which is crashing it) reveals that there are articles describing how to fix it. (such as this one, which says it is part of the Speech and Handwriting Recognition software in Microsoft XP and is probably not used by most people). --Fastfission 02:52, 25 June 2006 (UTC)[reply]
In MS Paint, you can drag the edge of the image (where the white canvas becomes grey) to make the image smaller. You can also use the lasso tool to move the image to the top-right of the canvas.  freshofftheufoΓΛĿЌ  06:52, 25 June 2006 (UTC)[reply]
  • I moved the image to one corner of the white canvas and made the canvas smaller by dragging the opposite corner inward.Patchouli 13:48, 25 June 2006 (UTC)[reply]
The best way to take a picture of only one (1) window, is to hold the mouse over its title bar and press Alt+PrtScn. --Andreas Rejbrand 10:03, 25 June 2006 (UTC)[reply]
If you have done so, and just want to save the window screenshot as an image file no larger than the window, you can resize the MS Paint canvas to a size even smaller than the window, and then paste. MS Paint will then (at your permission) resize the canvas so it will perfectly fit the window. --Andreas Rejbrand 10:07, 25 June 2006 (UTC)[reply]
Perhaps, to be very clear, we should explain why the answer has been "don't run beta software". I note that the original questioner seems to have ignored this answer, and kept on with the original expectation that there will be solution. So I hope this helps... not everyone knows what a "beta" is. I think some people think it is a way of saying "better". "Beta" software is software that is not ready. Not finished. Not of final quality. It is there for you to try, to find problems and report them. By reporting the problems, you help improve the quality of the final product. So using beta software can be interesting, and can benefit future users of the product. You should never be surprised if it crashes, and you can't expect to find a solution, but it is helpful to report crashes to the maker of the software. You should also always have an alternative plan, what to do if the beta software isn't any use to you. Notinasnaid 10:28, 25 June 2006 (UTC)[reply]

A very good idea would be to upgrade to Internet Explorer 7 Beta 3, released yesterday. --Andreas Rejbrand 21:59, 30 June 2006 (UTC)[reply]

  • I still don't think it has anything to do with IE, as that type of error usually relates to shared memory issues, which are notorious on Media Center Eddition PCs--205.188.116.67 02:23, 3 July 2006 (UTC)[reply]

remove coating[edit]

Can anyone give a simple household method for removing a lacquer (note not a glaze) from a ceramic?HappyVR 14:00, 24 June 2006 (UTC)[reply]

Abrade it with steel wool or sandpaper ? StuRat 14:43, 24 June 2006 (UTC)[reply]
Thanks but that isn't really an option - too many crevices for one reason - was really looking for a non-abrasive method (wet method?)HappyVR 14:58, 24 June 2006 (UTC)[reply]
Lacquer thinner? Maybe alcohol plus boiling water? --Proficient 18:02, 24 June 2006 (UTC)[reply]
I've tried boiling water, hot water with detergent, paint and varnish remover, petrol and white spirit. Not sure than Lacquer thinner will be any different. Can't really get any alcohol into boiling water - it just keeps boiling off..HappyVR 20:30, 24 June 2006 (UTC)[reply]

Gamma butyrolactone should do it... You can buy it as a superglue remover/debonder. Paint it on, and rub it off with a cloth covered in white spirit. --Eh-Steve 03:14, 25 June 2006 (UTC)[reply]

Doesn't seem to work.HappyVR 14:14, 25 June 2006 (UTC)[reply]
You tried Gamma butyrolactone and it didn't work? It should remove an acrylic lacquer within a few mins... In that case, it might help if you knew what the lacquer was. --Eh-Steve 13:46, 26 June 2006 (UTC)[reply]
Don't really know what it is except it's shiny.HappyVR 16:05, 30 June 2006 (UTC)[reply]

PC's Parellel Port Programming in C++[edit]

I have made a project of controlling a simple hardware by interfacing it with the 25pin D type connector(parellel port).It has 8 LED which i connected it parellely with the 8 bit data comming out from Data Register of the port but i want to run it sequencially or as desired by us or randomly sequence.the programme i used is as under.

#include<stdio.h>
#include<dos.h>
void main(void)
{outp(0x3BC,128);
 delay(100);
 outp(0x3BC,64);
 delay(100);
 return 0;
}

but the problem in it is that the delay command is not viewed or the sequence of first 128 and then 64 is not fllowed n it goes directly to 64.but it is not waiting for 128 and then go for 64.i saw the same by using sleep(n) command it also did not worked.do help me.

Are you sure your delay function is in seconds? Most delay/sleep functions are in milliseconds. Rare ones are in microseconds. I believe the unix sleep function is in seconds. 100 milliseconds isn't very long to wait (1/10th of a second). --Kainaw (talk) 18:33, 24 June 2006 (UTC)[reply]
Every .1 seconds seems like a reasonable (even high) time between pollings. However Kainaw is correct. --mboverload@ 04:35, 27 June 2006 (UTC)[reply]

Bios problems?[edit]

For some reason my computer seems to have started waiting for about 30 seconds doing apparently nothing when I reboot it. Well a screen saying "Compac V3.07" comes up, then it appears to just sit there. Eventually grub loads and then either XP or ubuntu boots up perfectly normally. This same thing happens if I have a floppy or DVD in the drive - do nothing for ages then boot from the floppy or DVD.

To get into the bios I have to hit f1 (I used to have to be quick but now I have plenty of time) instead going straight to the bios setup it again waits ages.

I have another problem which may or may not be related. Neither operating system properly sees my usb hard drive anymore. XP makes a ding dong noise when i switch it on and off so something is going on but no icon appears on the desktop and I can't see it in "my computer". in linux no icon appears on the desktop anymore.

I've had a quick look at the bios and i cant see anything glaringly obvious but I'm not an expert and don't know what to look for. Does anyone have any ideas? BTW I have recently gone from ubuntu "breezy badger" to "Dapper Drake" (but i can't see how that could affect anything that happens before the operating sytem boots) and i do occasionaly let young children play on my computer (but not recently) Theresa Knott | Taste the Korn 17:07, 24 June 2006 (UTC)[reply]

Well, if both OS's are affected it's bound to be a hardware problem. Have you tried booting without the usb drive connected? A wild guess is that the computer sees it, tries to connect, can't somehow, tries a few more times and then gives up after half a minute and boots. Does the drive show in the BIOS? DirkvdM 18:30, 24 June 2006 (UTC)[reply]
Could your BIOS have been set to allow booting from a network? If so, it would probably be waiting a bit to see if some server would like to deliver it some instructions. Or if it is set to allow boot from CD, it might be waiting till the drive says "hey, there's nothing here, just move along!" --LarryMac 21:32, 24 June 2006 (UTC)[reply]
Maybe a clean install will help. Or try to get a flash BIOS update so that your problems may be solved. Contact the manufacturer of your motherboard. --Proficient 22:04, 24 June 2006 (UTC)[reply]

Thanks for the replies. I've just tried removing the external hard drive and doing that solved the delay problem. Does that mean there is something physically wrong with the drive? I only got it 6 months ago. 86.7.146.177 23:18, 24 June 2006 (UTC)[reply]

Could be. Try plugging the hard drive into another computer. --Carnildo 05:39, 25 June 2006 (UTC)[reply]
Try getting a Mac. Trollderella 19:08, 30 June 2006 (UTC)[reply]
The problem is almost definitely GRUB under certain circumstances. GRUB usually loads quickly for me, but when I have my USB flash drive plugged in on boot, the line "GRUB loading... please wait..." stays there for a very long time. It's not my BIOS investigating the USB flash drive because by the time GRUB has started loading, BIOS has already tried to boot from the hard drive and doesn't care about anything else anymore. Therefore I infer that the problem must be GRUB and external drives. My theory is that GRUB scans all attached drives and their filesystems when it loads, and since USB flash drives typically have a slower transfer rate than hard drives, GRUB loads slowly. Many BIOSes don't show the lines GRUB prints when it loads for some reason, which might be why it seems to hang. I'd say the problem in your case is GRUB looking at your external hard drive, which has a slow transfer rate since it's external. -- Daverocks (talk) 09:52, 2 July 2006 (UTC)[reply]

Levorotary sugars?[edit]

Do L-form sugars cause sweet tastes? Are they metabolized by the body? Because if they are sweet and not processed, why are they not used more often as artificial sweeteners? --Zemylat 18:08, 24 June 2006 (UTC)[reply]

They don't taste sweet. The receptors on your tongue are chiral, so the wrong enantiomer doesn't fit into them. See Sweetness or google glucophore. —Keenan Pepper 18:14, 24 June 2006 (UTC)[reply]
A few minor asides. First, not all L- enantiomers are levorotatory. The D- and L- notation are based on the geometric configuration of the molecule rather than directly on their optical activity. See Optical isomerism#By configuration: D- and L-.
The (+) and (-) notation, in contrast, are directly related to dextro- and levo- rotation, and are sometimes specified as d- or l- isomers, leading to no end of notational confusion. To take an example, D-fructose is actually levorotatory, and equivalent to l-fructose or (-)-fructose—and it's definitely sweet.
Surprisingly, the relative sweetness of D- versus L- isomers is difficult to predict. There's a chap by the name of Gilbert Levin who started looking at L- isomers as artificial sweeteners back in the 1980s (late 70s, even?); he started a company called Spherix [2] that does this type of research. Levin found that people couldn't tell the difference between D- and L-glucose in taste tests. Unfortunately, producing large quantities of these L- isomers proved too costly for use in food products.
Levin's story does have a happy ending, in that he discovered that D-tagatose actually tasted as sweet as sugar but with only a third of the calories; he also developed a process to generate tagatose inexpensively from lactose and sold it to Arla Foods. To my knowledge there are no tagatose-containing food products on the market yet. TenOfAllTrades(talk) 18:56, 24 June 2006 (UTC)[reply]

Info Needed about Arrow International[edit]

Could someone give intimate information regarding Arrow International Medical company? I believe they are based out of Reading Pennsylvania and understand that they make catheters and balloon pumps, but more info would be appreciated.

Have you checked their website? --Kainaw (talk) 00:37, 25 June 2006 (UTC)[reply]

Hand swelling[edit]

Hi. I'm 19 year old and sometimes when I go out at night (and drink, though not heavily I lose some reflexes) I quite often feel swelling in my hands. This only happens recently, about one year ago I didn't have any problem. Any ideas? Thanks. —Preceding unsigned comment added by 85.50.40.204 (talkcontribs)

My suggestion would be to try abstaining from the consumption of alcoholic beverages, to determine whether alcohol is causing this problem. Consumption of beverage alcohol can cause numerous health problems -- see Alcohol_consumption_and_health and Effects_of_alcohol_on_the_body -- so it could easily be causing the symptoms that you are experiencing. If this doesn't help, you might want to consult with a physician. Good luck. John254 21:09, 24 June 2006 (UTC)[reply]
It happens also to me sometimes, when I am a bit dehydrated, which I think alcohol exacerbates. (Cj67 21:44, 24 June 2006 (UTC))[reply]
If you determine alcohol as the problem, then it's quite possible that dehydration is the reason for your swelling hands, as Cj67 says. Many people also experience swelling of the face when drinking even small amounts of alcohol. Drink lots of water in between drinks (to replace the fluids you've lost going to the toilet) and that might help.  freshofftheufoΓΛĿЌ  06:06, 25 June 2006 (UTC)[reply]
Well, that depends on what is most convenient. Whenever I've had a bit too much too drink I make sure to drink at least a litre of water before I go to bed to prevent a hangover. Works great (up to a point). DirkvdM 07:06, 25 June 2006 (UTC)[reply]

While on the subject of gulls again...[edit]

Anyone know why humans don't keep them as pets? Thnking about it, a gull would be very low maintenance, both in terms of food and care - and if raised from the egg, they can become very tame. --Kurt Shaped Box 21:20, 24 June 2006 (UTC)[reply]

For a start, gull droppings are one of the most evil substances known to man, and gulls need a large area to fly around. If not given regular access to the sea, they'd also probably start to behave crazily and attack people; gulls can get very violent. smurrayinchester(User), (Talk) 21:45, 24 June 2006 (UTC)[reply]
I once raised a baby gull. She was incredibly sweet, if a bit feisty at times. I had her living in my garden for six months once she was old enough to fly - she didn't want to leave. Can't say that the droppings were ever a problem - I just hosed them away every couple of days. I wouldn't advise keeping one in the house but I could recommend gulls to anyone - much less hassle than an outdoor rabbit (no piss for one thing). --Kurt Shaped Box 21:59, 24 June 2006 (UTC)[reply]
I've got this huge aviary with gulls, swans, koots, grebes, ducks, shags and what have you. All I need to do is look out the window. I live at an Amsterdam canal. :) DirkvdM 07:13, 25 June 2006 (UTC)[reply]